The present invention relates to a crane boom for transport as container freight which can be assembled from a plurality of boom parts which each have coupling pieces at the front-face end for the putting together of the boom parts, with the boom parts each having at least one bottom chord and being able to be put together such that the bottom chords of the boom parts together form a runway for a crab which is continuously free of misalignment and faults. The invention further relates to a transport apparatus for the transport of boom parts of a crane boom of this type as container freight. The invention finally relates to a container unit consisting of the boom parts of the crane boom and of a transport apparatus of this type.
The transport volume also plays a substantial role with cranes to be shipped due to the constantly increasing transport costs. As a rule, crane booms of tower cranes which commonly reach boom lengths of over 60 m are particularly bulky. Crane booms of this type of tower cranes, as a rule, have system similarity over the total boom length so that they can only be transported in a space-saving manner with difficulty.
A reduction in the transport volume and greater space utilization can be achieved with a telescopic boom in which the boom parts can be telescoped together.
Telescopic booms of this type, however, make a special crab shape necessary since the boom parts have to work with different bottom chord tracks for the crab in crane operation or have bottom chords offset in height to permit a pushing together. Telescopic booms of this type are relatively expensive. It is additionally necessary to design the construction of the crab such that it can either travel over the vertical faults or over the track width offset between the bottom chords of different boom parts.
In contrast, crane booms can be manufactured much more simply and also at a more favorable cost in which the boom parts can be put together sequentially by means of coupling pieces provided at the front face end. With crane booms of this type, the boom parts can be joined together such that the bottom chords connect to one another without offset or fault and a runway for the crab of the crane is formed beyond the intersection points between the boom parts which is continuously substantially free of offset or faults. However, the problem arises with crane booms of this type of being able to transport them in a space-saving manner since the boom parts correspond to one another as a rule so that they can only be placed next to one another. It is, however, hereby impossible to pack a crane boom in a standardized 40-foot container. As a rule, a plurality of containers have to be used or a plurality of transports carried out for the shipping of a crane boom.